The present invention generally relates to image projection systems. More particularly, the present invention relates to systems and methods for creating a three-dimensional image which appears to be suspended in air and which appears to be solid such that the different portions of the image can be viewed as one repositions himself around the image.
Creating images which appear to be suspended in the air are well known. For example, U.S. Pat. No. 4,979,026 to Lang et al. discloses a 360° viewing system for presenting an image in space that is rotated extremely rapidly so that an entire audience, regardless of an individual's position about the viewing system, can view the same image substantially simultaneously and continuously. An electronic image rotation system distorts, processes and rotates an image upon a cathode ray tube and a parabolic mirror arrangement which projects the image from the cathode ray tube to provide a rotating real image in space. A rotatable polarized screen and a separate stationary polarized screen cooperate to define a viewing window which remains continually aligned with the rotating real image in space.
U.S. Pat. No. 4,901,140 to Lang et al. is similar to U.S. Pat. No. 4,979,026, but utilizes a liquid crystal display screen to define a filtered viewing window which is continuously redefined at sequential intervals to remain continually aligned with the rotating real image in space.
U.S. Pat. No. 4,943,851 to Lang et al. discloses another viewing system for presenting a projected image upon a rear projection screen that is rotated extremely rapidly about a vertical axis which exactly bisects the picture in the vertical plane. The rotational rate is such that an entire audience, regardless of their position about the viewing system, can view the projected image simultaneously.
U.S. Pat. No. 6,072,545 to Gribschaw et al. discloses another image rotating apparatus which presents a projected video image upon a rear projection screen that is rotated extremely rapidly about a vertical axis such that an entire audience, regardless of their position about the apparatus can view the projected video image simultaneously. The video image rotating apparatus utilizes light valve technology to create red, green and blue images from an analog composite video signal, and a prism that aligns the images produced by the light valve for projection through an optical system. The image produced by the light valve is rotated in synchronization with the rotation of the projection screen.
U.S. Pat. No. 6,950,153 to Lane discloses a video imaging rotating apparatus which includes a rear projection screen rotatably disposed in a generally horizontal plane. Thus, only a single mirror which is angularly positioned over the screen can be used to project the video images to viewers.
Although the foregoing patents disclose various systems and methods for creating a video image such that an audience, regardless of their position about the apparatus, can view the same projected video image simultaneously, all of the foregoing systems and methods attempt to replicate what would be the equivalent of a television screen image. That is, the image is substantially two dimensional in character such that each member of the audience, regardless of position, views the exact same angle or image. Thus, for example, if a front of a car were being projected as an image, every audience member seated around the apparatus would view the front of the car nearly simultaneously. Thus, while these methods and systems overcome the disadvantage of having a single television screen associated with conventional image displays, these methods and systems do not present a true three-dimensional image in which various angles of the image can be viewed by repositioning the viewing angle of the individual viewing the image.
The creation of three-dimensional objects on a conventional two-dimensional display, such as a computer monitor or television is well known. However, only those immediately in front of the computer monitor or television screen can view the image, and rotation of the image using software is required to view the various angles of the three-dimensional image. Moreover, such methodologies and systems do not give the appearance of a three-dimensional object being suspended in space and viewable from different views and angles in all directions of a 360° angle by multiple members of an audience simultaneously.
Another well known three-dimensional approach is for the user to wear filtering glasses which present a stereoscopic-type display, wherein images from the television or projector screen appear to be three-dimensional. Once again, the viewer must be positioned immediately in front of the screen, and furthermore must wear the specially designed glasses in order to view such images, and the three-dimensional images are limited to the viewing angle in which they are created.
One of the earlier approaches of displaying a volumetric three-dimensional image was by the use of a Varifocal mirror. This consisted of a vibrating mirror and a stationary cathode ray tube (CRT). A series of cross-sectional images are displayed in sequence on this CRT, which, as viewed through a flexion from the vibrating mirror, form a volumetric three-dimensional image. However, this approach has a very limited view angle because the images are inside of the mirror.
Another type of display utilizes a rotating or reciprocating light emitting diode (LED) matrix. A sequence of two-dimensional cross-sectional images are displayed as the LED matrix rotates or moves in space to create the three-dimensional images. However, moving large area LED panels at high frequency creates reliability problems and signal coupling issues.
Another type of volumetric three-dimensional display uses the intersecting light spot of a scanning laser beam, or other electron beam, on a moving screen or disk which sweeps across a volume to generate three-dimensional images. However, such point scanning methodologies are seriously limited by data rate, resolution, brightness and color. As a result, only wire frame or course bit images are possible.
U.S. Pat. No. 5,954,414 to Tsao discloses an approach for displaying volumetric three-dimensional images. The method projects a series of frames of two-dimensional images, through an optical mechanical image delivery system, onto a translucent screen which moves periodically and sweeps a space. As viewed from outside the space, the series of two-dimensional images distributed in the space form a volumetric image because of the after-image effect of human eyes. Thus, many viewers can walk around the space and see the image from many angles simultaneously without wearing any kind of glasses.
U.S. Pat. No. 6,064,423 to Geng also discloses a process and system for creating volumetric three-dimensional images. The process and system utilizes a sequence of helical slices of three-dimensional data to generate a series of two-dimensional images on a reflective surface of a light modulator. These are projected into a volumetric three-dimensional space display using an illumination light source and projection optics. Once again, a three-dimensional image is generated which can be viewed from any angle in a walk-around manner without utilizing any viewing aids.
U.S. Patent Publication No. US 2006/0171008 A1 to Mintz et al. discloses another three-dimensional hologram display system. The projector device projects an image upon the display medium to form a three-dimensional hologram. The three-dimensional hologram is formed such that a viewer can view the holographic image from multiple angles up to 360°.
Although the Tsao, Geng and Mintz et al. processes and systems create a three-dimensional image which appears to be suspended in air and which can be viewed from 360°, the problem with such images is that they are holograms, meaning that they are transparent such that one views the front and back of the image at the same time. Thus, although a three-dimensional image is presented, it is clear to the human eye that such an image is not real, and instead appears to be holographic or transparent in nature.
Accordingly, there is a continuing need for systems and methodologies for creating a three-dimensional image which appears to be suspended in space, and which many viewers can walk around the space and see the image from multiple directions simultaneously without wearing any kind of glasses, and in a manner such that the angle of the image appears to be solid and realistic. The present invention fulfills these needs, and provides other related advantages.